Brake



1932- w. H. DELAHAYE BRAKE Filed Dec. 2. 1929 III/II WALTER H. DZLAHAYE.

' BY ATTORNEY Patented Aug. 30, 1932 'JEI. DELAHA'YE, 0F G'ITA'WA,GNTARIQ, GANA'DA, ASSIGNQR. TO IBENDIX BRAKE COMPANY, OF SOUTH BEND,INDIANA Application filed December 23, 1929. Serial No. 410,935.

on the ends of the brake shoes will show that these quite unequal when asymmetrical sod. Such a cum whenmoving into e position causes c thruston both 1 direction which is perellei to e cal to the brake drum andwhich to s redial line which posses L e sxis oi the cum shaft. But inuddi this erce, a considerable force exerted due to the. frictionalengagement n on the shoes and which acts in scion of movement of thecom. In

component augments the sponent oithe force but in the counteracts it.Nfhen the brakes his frictional component is smeii not so ohjectioneoie,but when the shoes have become worn and nt it smooth plane surface, c:onehie. 150G631 practice provide rollers he cum out it is the object ofthis to evoidthis more costly construcobtain it satisfactory operation 9throughout its useful his.

hy and hy way of example e sens "for carrying the invention It s s,sectional devotion of port of he showing the improved construeccm-engeging surface.

is diagram of the forces acting l ve-d type of shoe, and s is c similardiagram applied to the 'COiiliiTz-ufi type of shoe.

Retire once to Figure l wiil show that the two shoes end 2 have fistsurfaces 3 and iengeged hy n com 5 which operates in the direction shownby the arrow, to apply the shoes to the brake drum '8. It will be notedthat these surfaces 3 and 4: are not quite per- To overcome this it Wingetteched hereto shows dieellel, as they have been made heretofore, butat least, thet'surface which is engaged by that end of the corn whichmoves inwardly when operated to'npply the brake is inclined relativelyto the radial line 7 passing through the axis of the com. The advantagesof this construction will be apparent from the description of theoperation of com brakes otfered above. Y

Referring now to the diegrum shown in Figures 2 end 3, thenon-tangential thrustis represented by the line AB which in Figure 2 isnormal to the inclined com-engaging surface-4L The line BC shows thedirection of the frictional component on the inclined sur face, and theline AC shows a. resultant force which is parallel to the tangent end atright angles to e, redial iine 7. Such e. resultant avoids theobjectionable inward thrust on the shoe. Figure 3 shows the some forcesas they exist in the common. type oi brake and the difference in thedirection of the re suitsnt wiii be apparent.

In the drawing the inclination oi" the comengeging surface is shown asat e considersbie angle for the purpose of more cleariy iiiustrctinginvention. iin'practicc it maybe found that u suitehie angle is one thatis much smaller then that shown.

it wiii he understood that the invention may be eppiied to any type ofcsm-opersted broke and that the drawing" is purely exemplsry incherecten eli detsiis being omit bed for cieerness of iiiustrstion ofthe inention.

It will oiso be understood thet runny modii'icetions mey he made withinthe scope oi? the appended claims without deperting from the invention.

What I cieim is:

1. In a, cem-opereted broke, the combine,- tion of a, psir of shoes ende com "for expending some cemengeging surfaces on the shoes, one of saidsurfaces being so disposed in regard to the cam that the resultant ofthe expanding force and the inward forces due to the frictionalengagement of the cam on the shoe lies in a plane normal to the radialplane passing through the axis of the cam.

2. In e cum-operated brake the combine trenlity.

tion of a pair of shoes and a cam for expanding same, cam-engaginsurfaces on the shoes, the surface engaging that end of the cam whichhas an inward movement being so disposed in relation thereto that theinward force of the cam due to the frictional engagement between the camand the shoe is 'coun-' teracted. I v 3. A brake having the features setforth in claim 2, wherein the surface engaging the inwardly moving endof the cam is-inclined. to I the radial line passing through the axis of1 the cam and closest thereto at its outer ex- 4. A brake comprising afixed sup ort, a friction element positioned thereon aving separableends one ofwhich is inclined to the other, a cam so cooperating with theseparable ends that the force applied to the inclined end lies in aplane normal to a radial. plane of the fixed support passing through theaxis of the cam.

In testimony whereof I have aflixed my signature.

WALTER H. DELAHAYE.

